This new cultivar of Acer rubrum, the ‘JSC Kingstwo’ maple, was originally discovered as a naturally occurring limb mutation by James David Cavett in 2006 on one specific tree limb of an unnamed Acer rubrum tree planted in the yard of James D. Cavett at 74 S&W Lane, Estill Springs, Tenn. 37330. James D. Cavett took six cuttings off that single branch on the tree and rooted it in sand using Hormondin #3 (active ingredient is indole-3-butyric acid) at 74 S&W Lane, Estill Springs, Tenn. 37330 in July 2006. One of the 6 rooted cuttings survived. Sixty rooted cuttings were started from the 1 surviving rooted cutting in July 2007; these rooted cuttings were grown at 74 S&W Lane, Estill Springs, Tenn. Approximately 20 of the rooted cuttings begun in July 2007 survived and were used to begin 150 new rooted cuttings in July 2008 and 55 survived. In July 2009, approximately 250 rooted cuttings were taken and rooted in sand; approximately 125 rooted and survived. In July 2010, approximately 800 rooted cuttings were taken and rooted in sand; approximately 650 rooted and survived. In July 2011, approximately 2900 rooted cuttings were taken and rooted in sand; approximately 2000 rooted and survived. Over the last 5 years all the rooted cuttings of ‘JSC Kingstwo’ have exhibited the same growing characteristics and patterns as the parent tree, an unnamed Acer rubrum, except for the pigmentation of the leaves. The leaves of the rooted seedlings' pigmentation are reddish brown (172A-RHS) when the leaf breaks out of the bud. Within days of emerging from the bud, the reddish-brown color is surrounded by a light green (145A-RHS) pigmentation. As the leaf enlarges, portions of it become yellow (12A-RHS) until the large areas of the leaf become light yellow (8C-RHS) to whitish-yellow or cream (4D-RHS) color to white (N199D-RHS) mixed with green color (145A-RHS). Older growth leaves have speckles of cream (4D-RHS) on a dark-green background (137A-RHS). James D. Cavett has been evaluating these propagated seedlings for 5 years.
James D. Cavett is solely responsible for finding this new cultivar on his property, located at 74 S&W Lane, Estill Springs, Tenn. 37330. All propagation of this cultivar has been done by James D. Cavett at his nursery, located at 74 S&W Lane, Estill Springs, Tenn. 37330.
James D. Cavett immediately recognized that the new cultivar, ‘JSC Kingstwo’, exhibited new and distinctive leaf pigmentation. The leaves are reddish-brown when they first erupt from the bud. However, within days of emerging the leaf exhibits a mosaic of reddish-brown surrounded by a light green pigmentation. As the leaf enlarges and matures, the leaf pigmentation becomes whitish-yellow (cream) and a light green. The mature leaf exhibits cream color surrounded by dark green regions. All other growth characteristics of the cultivar are similar to the parent tree, an unnamed Acer rubrum. Only the seedlings that have originated from rooted cuttings of the original rooted stem that James D. Cavett rooted in 2006, exhibit the leaf pigmentation that is attributed to the new cultivar, ‘JSC Kingstwo’. Over the last five years, only the rooted cuttings have exhibited this pigmentation as compared to other Acer rubrum trees known to the Inventor.
As shown in the first two photographs (a 2-year old seedling taken Jun. 22, 2008, labeled FIGS. 1 & 2) of the ‘JSC Kingstwo’ cultivar, the pigmentation of the leaves is distinctive and unique. The leaves that are coming out of the apical bud are reddish-brown in color. The young leaves immediately below the apical leaves retain this reddish-brown color for up to a week but the reddish-brown is quickly surrounded by a light green color as chlorophyll is produced. Leaves further down the stem, have a variegated yellow-green, green-yellow, and light green color. More mature leaves are also variegated (FIG. 3) and exhibit muted yellowish-green regions in a background of dark green and cream pigmentation. Because the cultivar and the parent tree that it came from are deciduous, the leaves turn color (from pink [56A RHS] to a purple-pink [68A RHS]). Other regions of the leaf exhibit a light yellow (15D RHS) color. The leaves drop off each fall in Zone 6b, which includes Middle Tennessee.
As shown in the third photograph (a 3-year old tree taken June 2009, labeled FIG. 3) of the ‘JSC Kingstwo’ cultivar, the pigmentation of the leaves is distinctive and unique. As the tree matures, not all leaves will exhibit the same degree of variegation. Some leaves show more variegation than others. For example, some will have more cream color than others. However, mature late summer leaves exhibit a variegated cream and light green mixture of pigmentation surrounded by a dark green pigmentation. The leaf has red petioles.
As seen in more detail (see FIG. 4), the seedling has an opposite arrangement. The leaves are 5 cm to 8 cm (or 2.0 to 3.1 inches) in length and 7.6 cm to 16.5 cm (or 3.0 to 6.5 inches) in width. The leaves consist of 3 to 5 shallow lobes with shallow tooth margins. The petioles are red (47A-RHS) when the leaf first opens and remain red. The red petioles persist into the fall as the leaves change color (see FIGS. 5 & 6). The diameter of petioles are ˜0.3 to 0.4 cm and vary in length from 2 cm to 3.5 cm.
FIGS. 5 and 6 show the characteristic colors that the fall leaves take on. In early fall, the green chlorophyll begins to break down and is replaced by a light pink (56A-RHS) hue in the cream-colored portions of the leaf that spreads into the once green-pigmented regions giving it a purple-pink (68A-RHS) color (FIG. 5). By late fall, the leaf color becomes predominately red-brown (179B-RHS) with small areas of the leaf still exhibiting the light cream color that was first seen in the early spring several days after the leaf emerged for its bud. The petiole remains red (47A-RHS).
There are several flower buds at the end of each stem (see FIG. 7) that emerge in early spring (usually the end of February to early March in middle Tennessee) revealing sterile flowers that consist of 4 to 10 stamen that are yellow-green (145B-RHS) on yellow (23A-RHS) stalks. The flowers are encased in burgundy-red (45A-RHS) sepals before the flower emerges.
The ‘JSC Kingstwo’ cultivar has proven to be both drought resistant and winter hardy. From mid-May until mid-June 2011, Middle Tennessee (climate Zone 6b, USDA Plant Hardiness Zone Map) experienced an unusual spring drought and for the first two weeks of June 2011, Middle Tennessee experienced the hottest first two weeks recorded in Tennessee in June in decades. This was a particularly dangerous and damaging drought coupled with extreme heat because most of the trees had already budded. The ‘JSC Kingstwo’ cultivar survived this drought and extremely hot weather and continued to produce foliage throughout the spring and summer months. All rooted cuttings taken from the trees exhibit the same moderate growth that has been observed for the previous seasons that the ‘JSC Kingstwo’ cultivar has been cultivated.
The ‘JSC Kingstwo’ cultivar can also endure drastic changes in moisture. ‘JSC Kingstwo’ cultivar has been successfully grown without irrigation after it was moved into the fields during its third season. Each summer since it was rooted in 2006, it has endured the drought that Middle Tennessee has experienced during the months of July and August. However, this spring (2011) we had an unusual drought in Middle Tennessee between mid-May to mid-June. The cultivar survived this early spring drought without any irrigation.
The ‘JSC Kingstwo’ cultivar has been successfully propagated asexually. The proven means of asexual propagation has been rooted softwood cuttings. During the first year, the stem that was discovered by James D. Cavett was rooted as six cuttings in sand at his nursery at 74 S&W Lane, Estill Springs, Tenn. 37330; hence, only 6 cuttings were stuck in sand in 2006. In July 2007, 1 rooted cutting survived and was used to start 60 rooted cuttings in sand in July 2007 by James D. Cavett at his nursery. In July 2008, approximately 20 of 60 rooted cuttings that survived were used to begin 150 new rooted cuttings and 55 survived. In July 2009, 250 rooted cuttings were taken and rooted in sand; approximately 125 survived. In July 2010, 800 rooted cuttings were begun and approximately 650 survived. Approximately 2900 rooted cuttings were stuck in sand in July 2011 and 2000 survived. The cultivars have retained all the characteristics of the original selected seedling. It has been successfully propagated through 5 generations of asexual reproduction with a survival rate between 33% the second year (2007), 37% the third year (2008), 50% the fourth year (2009), and a 81% survival rate in the fifth year (2010). 69% of the cuttings have survived in 2011. Each generation has been stable and produced true-to-type trees each and every time the tree has been propagated.
The unique color of the leaves and moderate growth (3 to 6 feet per year) of ‘JSC Kingstwo’ cultivar make it well suited for a variety of landscaping uses. Furthermore, the ‘JSC Kingstwo’ cultivar is cold and drought tolerant. The cultivar is a moderate size tree whose leaf pigmentation is reddish-brown (172A-RHS) followed by a variegated light yellow (8C-RHS) to cream (4D-RHS) and white (N199D-RHS) surrounded by a light green (145A-RHS) color in the weeks following their emergence from the bud. The mature leaf exhibits a variegated cream (4D-RHS) with a splash of light yellow (8C-RHS) and dark-green (137A-RHS) color. In the fall, the leaves turn from a variegated cream on a green background to a purple-pink (68A-RHS) mixture consisting of reds and pinks with a light yellow (12A-RHS) in the creamy variegated portion of the leaf (see FIG. 5) until the green pigmentation is replaced by the pink and purple-pink (68A-RHS) color interspersed with the variegated light cream color (see FIG. 6). The unique color of the leaves of the ‘JSC Kingstwo’ cultivar will make it a popular maple tree for those who desire attractive coloration from early spring through the fall.